Assessing the physical state of the Fore-topsail of HMS Victory

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Description/Abstract

Marine textiles form a vital part of our cultural heritage. Some extant sails and surviving sail fragments in
museum collections are hundreds of years old. The Victory sail, from the early 19th century, was not only subject to the
ravages of the marine environment during its working life but has since suffered further deterioration during storage and
display.

To determine the optimum protocol for future conservation, display and storage, it was essential to determine its current physical state. The physical properties of sailcloth are influenced by a number of factors, many of which relate to its complex hierarchical structure. The Victory sail is composed of linen, a bast fibre comprised of cells reinforced with fibrillar microcrystalline cellulose within hemicellulose and pectin matrices. Lignin serves to cement aggregates of these ‘ultimate’ cells together.

At the higher levels of the hierarchy, fibre bundles are spun together as yarns, which in turn form the weave structure of
the cloth. To assess the current state of these fibres, physical properties of yarns from the Victory sail and appropriate surrogate materials were determined. Additional destructive tests on surrogates suggested a good correlation between the characteristics of individual yarns and of the bulk sailcloth. As a result it was possible to suggest loading limits for the Victory
sail. Further non-destructive slippage tests performed directly on the sail also proved crucial to informing decisions on
appropriate arrangements for display.

Examination by electron microscopy revealed a variety of features that correlated with the mechanical data: defects and
defibrillation were apparent in the more highly degraded specimens, as were surface debris and evidence of mould growth. When ruptured fibres were investigated, it was found that fractures appeared to propagate in a manner that could be linked to the degree of deterioration.